CN111372991B

CN111372991B - Flame retardant poly (vinyl chloride) composites

Info

Publication number: CN111372991B
Application number: CN201880067605.9A
Authority: CN
Inventors: 克雷格·L·休梅克; 阿姆贾德·阿布-阿利
Original assignee: Ji'ang Functional Materials Dongguan Co ltd
Current assignee: Ji'ang Functional Materials Dongguan Co ltd
Priority date: 2017-09-15
Filing date: 2018-09-11
Publication date: 2023-11-17
Anticipated expiration: 2038-09-11
Also published as: CA3075852C; US11339233B2; CN111372991A; WO2019055426A1; US20200216586A1; CA3075852A1

Abstract

The present application relates to plasticized poly (vinyl chloride) composites formulated to provide sufficient flexibility and flame retardancy to be suitable for use in building and construction polymer articles. One aspect of the present application is a flame retardant poly (vinyl chloride) compound comprising a mixture of: poly (vinyl chloride); a plasticizer selected from the group consisting of polymeric plasticizers, alkylaryl flame retardant plasticizers, and combinations thereof; and optionally a functional additive, wherein the mixture has: i) A limiting oxygen index according to ASTM D2863 of greater than 50%; ii) an elongation at break according to ASTM D638 (type IV) of at least 10%; and iii) an elastic modulus according to ASTM 638 (type IV) of less than about 15000 psi.

Description

Flame retardant poly (vinyl chloride) composites

Priority claim

The present application claims the benefit of U.S. provisional patent application Ser. No. 62/559,252, attorney docket No. 12017016, filed on 9/15 of 2017, which is hereby incorporated by reference in its entirety.

Technical Field

The present application relates to the use of plasticized poly (vinyl chloride) composites for purposes such as flexible flame retardant polymer building and construction products.

Background

People benefit from plastic articles. Thermoplastic polymers have become a component of many consumer products since their application in the middle of the 20 th century. Such products are relatively lightweight, strong and corrosion resistant.

Plasticized poly (vinyl chloride) invented by Waldo Semon of b.f. goodrich was a top performance plastic resin for decades. Billions of kilograms of poly (vinyl chloride) (also known as "PVC") resin are molded and extruded into countless products each year. With conventional additives, poly (vinyl chloride) provides, for example, unparalleled durability, flame retardancy, chemical resistance, weather resistance, electrical properties, and transparency.

Wire and cable manufacturers often use plasticized PVC for insulation and cladding in building and construction environments. Based on the accelerated oven aging test, the properties of plasticized PVC compounds at various temperatures are predicted. The Underwriters' Laboratories (UL) cable rated at 60 ℃ was tested at 100 ℃ for 7 days, while the 75 ℃ cable was tested at 100 ℃ for 10 days. Some of the plasticizers conventionally used are phthalates, citrates, soyates and trimellitates.

For other types of materials used in building and construction environments, ASTM International (www.astm.org) sets stringent standards for testing the surface combustion characteristics of building materials: "ASTM E84-15a Standard test method for Combustion characteristics of building Material surfaces". "the E84 test relates to a combustion-test-response criterion for comparative surface combustion behavior of construction materials suitable for exposed surfaces, such as walls and ceilings. The E84 test is performed in such a case: the sample is in the ceiling position and the surface to be evaluated is exposed face down to the ignition source. To meet the requirements of the E84 test, a material, product or assembly should be able to be installed in a test location during testing. Thus, the sample should be self-supporting by its structural properties, held in place by the addition of a support along the test surface, or fixed from the back.

Disclosure of Invention

What is needed in the art is a plasticized PVC compound that is flexible and that can be tested by E84 as described above. The harder the poly (vinyl chloride) composite, the easier it is to pass the E84 test. But if the poly (vinyl chloride) compound is reconstituted for the desired flexibility in this case, it is more difficult to pass the E84 test.

Thus, plasticized PVC compounds require careful balancing of ingredients to be flame retardant and flexible.

One aspect of the present application is a flame retardant poly (vinyl chloride) compound comprising a mixture of: (a) poly (vinyl chloride); (b) A plasticizer selected from the group consisting of (1) a polymeric plasticizer, (2) an alkylaryl flame retardant plasticizer, and combinations thereof; and optionally (c) a functional additive, wherein the mixture has a limiting oxygen index according to ASTM D2863 of greater than 50%; an elongation at break according to ASTM D638 (type IV) of at least 10%; and an elastic modulus according to ASTM 638 (type IV) of less than about 15000 psi.

Another aspect of the present application is a building and construction article made from the poly (vinyl chloride) composite described above.

Drawings

Fig. 1 is a photograph of a test panel (plaque) of example 4.

Detailed Description

Poly (vinyl chloride) resin

Polyvinyl chloride polymers are widely available worldwide. The polyvinyl chloride resin as referred to in the present specification includes: polyvinyl chloride homopolymers, vinyl chloride copolymers, graft copolymers and vinyl chloride polymers polymerized in the presence of any other polymer (e.g., HDT deformation temperature increasing polymer), impact toughening agent, barrier polymer, chain transfer agent, stabilizer, plasticizer or flow modifier.

For example, PVC polymers may be modified in combination by over-polymerizing a low viscosity, high glass transition temperature (Tg) enhancing agent, such as SAN resin or imidized polymethacrylate, in the presence of a chain transfer agent.

In another alternative, vinyl chloride may be polymerized in the presence of the Tg enhancer, which is formed prior to or during the polymerization of vinyl chloride. However, only those resins having a particular average particle size and degree of brittleness exhibit the advantages that are suitable for the practice of the present application.

In the practice of the present application, a polyvinyl chloride homopolymer or copolymer of polyvinyl chloride comprising one or more comonomers copolymerizable therewith may be used. Suitable comonomers for vinyl chloride include: acrylic acid and methacrylic acid; esters of acrylic and methacrylic acid wherein the ester moiety has 1 to 12 carbon atoms, such as methyl acrylate, ethyl acrylate, butyl acrylate, ethylhexyl acrylate, and the like; methyl methacrylate, ethyl methacrylate, butyl methacrylate, and the like; hydroxyalkyl esters of acrylic acid and methacrylic acid, such as hydroxymethyl acrylate, hydroxyethyl methacrylate, and the like; glycidyl esters of acrylic and methacrylic acid, such as glycidyl acrylate, glycidyl methacrylate, and the like; alpha, beta unsaturated dicarboxylic acids and anhydrides thereof, such as maleic acid, fumaric acid, itaconic acid, anhydrides thereof, and the like; acrylamide and methacrylamide; acrylonitrile and methacrylonitrile; maleimides, such as N-cyclohexylmaleimide; olefins such as ethylene, propylene, isobutylene, hexene, and the like; vinylidene chloride, such as vinylidene chloride; vinyl esters, such as vinyl acetate; vinyl ethers such as methyl vinyl ether, allyl glycidyl ether, n-butyl vinyl ether, and the like; crosslinking monomers such as diallyl phthalate, ethylene glycol dimethacrylate, methylenebisacrylamide, triacryloyltriazines, divinyl ethers, allylsilanes and the like; and mixtures comprising any of the foregoing comonomers.

Chlorinated polyvinyl chloride (CPVC) can also be used in the present application, wherein PVC containing about 57% chlorine is further reacted with chlorine radicals generated by chlorine gas dispersed in water and irradiated to generate chlorine radicals dissolved in water to produce polymer CPVC having a higher glass transition temperature (Tg) and heat distortion temperature. Commercial CPVC generally comprises from about 58% to about 70% by weight and preferably from about 63% to about 68% chlorine. CPVC copolymers can be obtained by chlorinating such PVC copolymers using conventional methods, such as those described in U.S. Pat. No. 2,996,489, incorporated herein by reference. Commercial sources of CPVC include Lubrizol Corporation.

Preferably of polyvinyl chloride homopolymer composition.

Commercially available sources of polyvinyl chloride polymers include the Oxy vinyl LP of Dallas, TX; and Freeport, sheintech USA of TX.

PVC composite

Flexible PVC resin composites typically contain various additives selected according to the performance requirements of the articles made therefrom, well within the purview of those skilled in the art without undue experimentation.

Plasticizer(s)

Non-limiting examples of plasticizers commonly used with poly (vinyl chloride) are phthalates, citrates, soyates and trimellitates. In this case two specific plasticizers are currently preferred.

A currently preferred plasticizer is Palamoll ^TM 654, which is a mixture sold by BASF as follows: adipic acid with the following polymers: 1, 4-butanediol and 2, 2-dimethyl-1, 3-propanediol, isononyl ester. The plasticizer was phthalate-free (considering current market conditions) and registered as CAS number 208945-12-4.

Another presently preferred plasticizer is Santicizer ^TM 2148 of plasticizer sold by Valtris and registered as CAS number 27460-02-2.

A polymeric plasticizer or an alkylaryl plasticizer may be used as the sole plasticizer for the flame retardant PVC composite. Alternatively, the two plasticizers may be combined in any ratio therebetween.

The presently preferred plasticizer, whether alone or in combination, ranges from about 115 parts to 130 parts by weight per 100 parts of PVC polymer.

Other functional additives

According to the experimental results described in the examples, the PVC compound used herein may contain an effective amount of an additive.

The poly (vinyl chloride) composites disclosed herein suitable for use in building and construction environments where E84 testing is required comprise:

the amount of calcium-zinc heat stabilizer, if present, is from about 1 part to about 4 parts per 100 parts PVC;

alumina trihydrate flame retardant, if present, in an amount of about 320 parts to 380 parts per 100 parts PVC;

the amount of zinc borate flame retardant (if present) is about 20 parts to 30 parts per 100 parts PVC;

included in Mg (OH) ₂ The amount of smoke suppressant (if present) of the above basic zinc molybdate complex is 3 to 8 parts per 100 parts PVC;

the amount of calcium carbonate functional filler, if present, is from about 150 parts to about 300 parts per 100 parts PVC;

the amount of stearic acid lubricant (if present) is from about 0.25 parts to about 0.75 parts per 100 parts PVC; and

the amount of carbon black pigment, if present, is from about 2 parts to about 5 parts per 100 parts PVC.

The compounds disclosed herein may contain other conventional plastic additives in amounts sufficient to obtain the desired processing or performance characteristics of the compound. The amount should not waste additives nor be detrimental to the processing or performance of the compound. Without undue experimentation and as referred to, for example, in Plastics Design Library (www.elsevier.com)Plastics Additives Database(2004) In the context of the paper, a person skilled in the art of thermoplastic compounding may choose from many different types of additives for inclusion in the compounds of the application.

Non-limiting examples of other optional additives include: an adhesion promoter; antimicrobial agents (antibacterial, bactericidal and antifungal agents); an antifogging agent; an antistatic agent; a binder, a foaming agent, and a foaming agent; a dispersing agent; fillers and extenders; fire and flame retardants and smoke suppressants; an impact modifier; an initiator; a lubricant; mica; pigments, colorants, and dyes; a plasticizer; a processing aid; a release agent; a silane; titanates and zirconates; slip agents and anti-blocking agents; a stabilizer; a stearate; an ultraviolet absorber; a viscosity modifier; a wax; and combinations thereof.

Processing

The preparation of the complexes of the application is as follows. The compounds of the present application may be prepared in batch or continuous operation from powder blends that are typically prepared in batch operation.

Such powder blending in a batch process is typically performed in a powder mixer, such as a Henschel or Littleford mixer, or a ribbon blender, that physically mixes all additives, including liquid plasticizers, with the PVC resin without bringing the polymer matrix to a melting temperature. The mixing speed ranges from 60rpm to 3000rpm and the mixing temperature may range from ambient up to 250°f (121 ℃). The output of the mixer is a well-blended powder product that can flow into a machine that can raise the blending temperature to cause some of the ingredients (including the PVC resin) to melt.

Mixing in a batch process is typically performed in a Banbury mixer, which is also raised to a temperature sufficient to melt the polymer matrix to allow the addition of the solid component additives of any optional additives. The mixing speed ranges from 60rpm to 3000rpm and the mixing temperature ranges from 250°f to 430°f (120 ℃ to 220 ℃), typically 325°f (163 ℃). The molten mixture was then placed on a 320℃F/345℃F (160℃to 174 ℃) twin roll mixer. The material was compounded for about four minutes, and then the compounded ribbon was cut into cubes for subsequent extrusion or molding into polymeric articles. Alternatively, for experimental evaluation, the compounded tape may be formed into a plate by compression molding for physical testing purposes.

The composite may be formed into a powder, cube or pellet for further extrusion into a profile or sheet form, with or without subsequent forming into polymeric parts and components.

Extrusion and molding techniques are well known to those skilled in the art of thermoplastic polymer engineering. Without undue experimentation, and with references such as "Extrusion, the Definitive Processing Guide and Handbook", "Specialized Molding Techniques" and "Handbook of Mold, tool and Die Repair Welding" published by Plastics Design Library (www.elesevier.com), the composites of the present application can be used to make articles of any desired shape and appearance. Non-limiting examples are polymeric articles that are reshaped in melt form into extrusion, molding, thermoforming, calendaring, or 3D printing.

For the E84 test, calendered, thermoformed, or other high aspect ratio polymeric articles can be made.

Utility of the application

The building and construction markets may benefit from the PVC composites disclosed herein. With sufficient flame retardancy to pass the E84 test and also sufficient flexibility to be used as a building or construction material, the space occupation can utilize these composites in a variety of shapes. For example, the profile extruded part may be complementary to a high aspect ratio part, both from the same or similar compounds disclosed herein. In addition, post-forming of films, sheets, panels, etc. can be used for both ceiling and wall construction.

As previously described, rigid poly (vinyl chloride) can be tested by E84. But rigidity is not preferred in construction and construction. Increasing the flexibility of poly (vinyl chloride) increases the usefulness of PVC composites in construction and construction, but reduces the likelihood of passing the E84 test. As demonstrated by the examples and comparative examples, a very good balance of ingredients was found to result in successful candidates for flexible, flame retardant building and construction products.

Examples

Table 2 shows the ingredient sources of the examples and all comparative examples. Table 3 shows the processing conditions used to make all experimental samples.

TABLE 3 processing Specification
	#1 roll mixer
All ingredients are weighed together into a container
	Thoroughly mixed and then kneaded at 320℃to 335℃F. (160℃to 168 ℃) for 4 minutes
Compression pressing at 345°f (174 ℃) to form boards for physical testing

Table 4 identifies the physical tests performed.

*0.63cm thick sample

*5.08cm x 508cm x 0.63cm samples

*15.2 cm. Times.15.2 cm. Times.1.9 cm samples

*15.2 cm. Times.15.2 cm. Times.0.32 cm samples

Table 5 shows the formulation and physical properties of the examples and comparative examples.

Six of the ten formulations were able to meet the flexibility and flame retardancy conditions.

All ten formulations had the same amounts of PVC polymer, heat stabilizer, zinc borate flame retardant, smoke suppressant and carbon black. Thus, the plasticizer content, alumina trihydrate flame retardant, stearic acid, and calcium carbonate filler are different.

For comparative examples a to B and examples 1, 2 and 5, the Santicizer 2148 aryl phosphate flame retardant plasticizer was not used. One difference between examples 1 and 2 and comparative examples a and B is that the Palamoll 654 polymer plasticizer fraction is higher, which results in a slightly lower limiting oxygen index but a higher percent elongation (and acceptable). The difference between comparative example a and example 5 is the amount of lubricant, which results in a significant difference in elongation results, although the elastic moduli are all within an acceptable range of less than 15000 psi.

The total plasticizer content of comparative examples a and B and examples 5 and 6 was 115 parts, while the plasticizer was present in a total of 127 parts for each of examples 1 to 4 and comparative examples. The satisfaction of three criteria of elastic modulus, elongation and limiting oxygen index distinguishes examples 1 to 6 from comparative examples a to D.

The use of Palamoll 654 plasticizer or Santicizer 2148 plasticizer (also having flame retardant properties) or both also provides the difference of examples 1 to 6. Examples 1, 2 and 5 used only the former, while example 6 used only the latter.

Comparative examples C to D and examples 3 and 4 Paramoll were tested at a ratio of 67:33 (2:1) and 50:50 (1:1) ^TM 254 plasticizer to Santicizer 2148 plasticizer. Comparison of comparative example C with example 3 and comparison of comparative example D with example 4 are consistent at the two ratios tested by examples 3 and 4, providing not only slightly higher modulus of elasticity results but also significantly higher percent elongation. The difference between the two pairs is that the amount of alumina trihydrate flame retardant present in examples 3 and 4 is 20% greater relative to comparative examples C and D, respectively.

As between example 3 and comparative example D, the ratio of the two types of plasticizers was 1:1, and the Limiting Oxygen Index (LOI) test (used to predict the passage of the E84 test) provided the basis for distinguishing between the two sets of physical properties. The LOI results of example 3 are 20% better than those of comparative example D.

While both comparative examples a and B do have higher LOIs than any of the examples, it is the balance of physical properties that must be established for successful building and construction polymer articles contemplated in the present disclosure.

Only the formulations of examples 1 to 6 meet the following criteria (and the current preferences for the criteria in examples 1 to 6):

an limiting oxygen index according to ASTM D2863 of greater than 50% (and currently preferably greater than 55%);

elongation at break according to ASTM D638 (type IV) is at least 10% (and currently preferably at least 20%); and

an elastic modulus according to ASTM 638 of less than about 15000 (type IV) (and presently preferred less than about 10000.)

Operating within all three criteria with their current preferences, example 4 is presently preferred. Fig. 1 shows a photograph of the flexibility of example 4, in which the opposite edges are in contact due to the constraint of the metal binder clip.

Other physical characteristics may be adjusted according to business or manufacturing preferences. For example, the specific gravity may be increased using additional calcium carbonate filler or using additional different filler (e.g., copper or tungsten metal particles or both).

Without undue experimentation and using the results of the experiments, one of ordinary skill in the art will be able to formulate a formulation suitable for achieving the physical properties of flame retardant, flexible PVC compounds within acceptable and preferred standards, respectively.

The present application is not limited to the above-described embodiments. The appended claims.

Claims

1. A flame retardant poly (vinyl chloride) compound comprising:

a mixture of the following components:

(a) Poly (vinyl chloride) (PVC);

(b) A plasticizer selected from the group consisting of:

(1) A polymeric plasticizer, wherein the polymeric plasticizer is a polymer of adipic acid as a mixture with: 1, 4-butanediol and 2, 2-dimethyl-1, 3-propanediol, isononyl ester,

(2) Alkylaryl flame retardant plasticizer, and

(3) A combination thereof; and

(c) The functional additive is added into the mixture to prepare the functional additive,

wherein the plasticizer, alone or in combination, ranges from 115 parts to 130 parts by weight per 100 parts of PVC polymer,

wherein the functional additive comprises both a calcium-zinc heat stabilizer in an amount of 1 to 4 parts per 100 parts of PVC, an alumina trihydrate flame retardant in an amount of 320 to 380 parts per 100 parts of PVC, a zinc borate flame retardant in an amount of 20 to 30 parts per 100 parts of PVC, a basic zinc molybdate complex smoke suppressant in an amount of 3 to 8 parts per 100 parts of PVC on magnesium hydroxide, a calcium carbonate density adjusting filler in an amount of 150 to 300 parts per 100 parts of PVC, a stearic acid lubricant in an amount of 0.25 to 0.75 parts per 100 parts of PVC, and a carbon black pigment in an amount of 2 to 5 parts per 100 parts of PVC, and

provided that the amount of the stearic acid lubricant is 0.25 parts to less than 0.50 parts per 100 parts of PVC when the weight parts of the plasticizer are 115 parts per 100 parts of PVC polymer,

wherein the mixture has a limiting oxygen index according to ASTM D2863 of greater than 50%; an elongation at break according to ASTM D638 type IV of at least 10%; and an elastic modulus according to ASTM 638 type IV of less than 15000 psi.

2. The flame retardant poly (vinyl chloride) compound of claim 1, wherein the limiting oxygen index is greater than 55%.

3. The flame retardant poly (vinyl chloride) compound of claim 1 or claim 2, wherein the elongation at break is at least 20%.

4. The flame retardant poly (vinyl chloride) compound of claim 1 or claim 2, wherein the elastic modulus is less than 10000psi.

5. The flame retardant poly (vinyl chloride) compound of claim 1 or claim 2, wherein the poly (vinyl chloride) comprises a poly (vinyl chloride) homopolymer.

6. The flame retardant poly (vinyl chloride) compound of claim 1 or claim 2, wherein the plasticizer comprises a polymeric plasticizer registered as CAS number 208945-12-4.

7. The flame retardant poly (vinyl chloride) compound of claim 1 or claim 2, wherein the plasticizer comprises a halogen-free, alkylaryl flame retardant plasticizer.

8. The flame retardant poly (vinyl chloride) compound of claim 1 or claim 2, wherein the plasticizer comprises an aryl phosphate ester registered as CAS number 27460-02-2.

9. The flame retardant poly (vinyl chloride) compound of claim 1 or claim 2, wherein the plasticizer comprises both a plasticizer registered as CAS number 208945-12-4 and a plasticizer registered as CAS number 27460-02-2, wherein both plasticizers are at 99:1;90:10;75:25;67:33;60:40;50:50;40:60;33:67;25:75;10:90; a ratio of 1:99; and each ratio combination between any two ratios so listed.

10. The flame retardant poly (vinyl chloride) compound of claim 9, wherein the two plasticizers are CAS number 208945-12-4 and CAS number 27460-02-2 combined in a ratio of 75:25 to 25:75.

11. The flame retardant poly (vinyl chloride) compound of claim 9, wherein the two plasticizers are CAS number 208945-12-4 and CAS number 27460-02-2 combined in a ratio of 67:33 to 33:67.

12. The flame retardant poly (vinyl chloride) compound of claim 1, wherein the mixture has a limiting oxygen index according to ASTM D2863 of less than or equal to 82%.

13. The flame retardant poly (vinyl chloride) compound of claim 1, wherein the mixture has an elongation at break according to ASTM D638 type IV of less than or equal to 43%.

14. The flame retardant poly (vinyl chloride) compound of claim 12, wherein the mixture has an elongation at break according to ASTM D638 type IV of less than or equal to 43%.

15. The flame retardant poly (vinyl chloride) compound of claim 1, wherein the mixture has an elastic modulus according to ASTM 638 type IV of at least 5,400 psi.

16. The flame retardant poly (vinyl chloride) compound of claim 12, wherein the mixture has an elastic modulus according to ASTM 638 type IV of at least 5,400 psi.

17. The flame retardant poly (vinyl chloride) compound of claim 14, wherein the mixture has an elastic modulus according to ASTM 638 type IV of at least 5,400 psi.

18. The flame retardant poly (vinyl chloride) compound of claim 1, wherein the plasticizer comprises a polymeric plasticizer, wherein the polymeric plasticizer is a polymer of adipic acid as a mixture with: 1, 4-butanediol and 2, 2-dimethyl-1, 3-propanediol, isononyl ester.

19. The flame retardant poly (vinyl chloride) compound of claim 1, wherein the plasticizer comprises an alkylaryl flame retardant plasticizer.

20. The flame retardant poly (vinyl chloride) compound of claim 1, wherein the plasticizer comprises a polymeric plasticizer and an alkylaryl flame retardant plasticizer.

21. The flame retardant poly (vinyl chloride) compound of claim 20, wherein the mixture has:

a limiting oxygen index according to ASTM D2863 of greater than 50% and less than or equal to 82%;

an elongation at break according to ASTM D638 type IV of at least 10% and less than or equal to 43%; and

an elastic modulus according to ASTM 638 type IV of at least 5,400psi and less than 15,000 psi.

22. The flame retardant poly (vinyl chloride) compound of claim 20, wherein the poly (vinyl chloride) comprises a poly (vinyl chloride) homopolymer.

23. A polymeric article comprising the flame retardant poly (vinyl chloride) composite according to any one of claims 1 to 9.